Polycarbonate resin compositions and articles therefrom

Abstract

A transparent, flame retardant polycarbonate composition consisting essentially of an aromatic polycarbonate resin and a flame-retarding amount of a guanidine salt or derivatives thereof, wherein the amount of guanidine salt or derivatives thereof is about 1 wt. % or less.

We claim:  
     
       1. A thermoplastic resin composition, consisting of: 
       a) an aromatic carbonate resin, and  
       b) a guanidine salt, derivatives or mixtures thereof, present in an amount of less than 1 wt. % based on the total weight of the composition.  
     
     
       2. The composition of  claim 1 , wherein said aromatic carbonate resin is selected from the group consisting of homopolymers, copolymers, linear polycarbonate resins, branched polycarbonates resins, and mixtures thereof. 
     
     
       3. The composition of  claim 1 , wherein said guanidine salt is an inorganic salt. 
     
     
       4. The composition of  claim 1 , wherein said guanidine salt or derivatives is selected from the group consisting of aminoguanidine nitrate, guanidine nitrate, triaminoguanidine nitrate, diaminoguanidine nitrate, guanidine carbonate, guanidine BPA, guanidine hydrochloride, guanidine bisulfite, guanidine sulfate, guanidine sulfamate, guanidine phosphate, guanidine hydrobromide, and mixtures thereof. 
     
     
       5. The composition of  claim 1 , wherein said guanidine salt, derivative, or mixture thereof is present in an amount of about 0.001 wt. % to about 0.5 wt. % based on the total weight of the composition. 
     
     
       6. The composition of  claim 1 , wherein said guanidine salt, derivative or mixture thereof is present in an amount of about 0.001 wt. % to about 0.01 wt. % based on the total weight of the composition. 
     
     
       7. A method for making a themoplastic resin composition with excellent flame retardant characteristics when tested according to French norm NF-P-92-505, said method comprising: 
       a) preparing an aromatic carbonate resin, and  
       b) melt blending the aromatic resin produced in step a) with a guanidine salt, derivatives, or mixtures thereof present in an amount of about 0 001 wt % to about 0.5 wt %, based on the total weight of the composition.  
     
     
       8. The method of  claim 7 , wherein said guanidine salt or derivative is selected from the group consisting of aminoguanidine nitrate, guanidine nitrate, triaminoguanidine nitrate, diaminoguanidine nitrate, guanidine carbonate, guanidine BPA, guanidine hydrochloride, guanidine bisulfite, guanidine sulfate, guanidine sulfamate, guanidine phosphate, guanidine hydrobromide, and mixtures thereof. 
     
     
       9. An article prepared from the flame retardant molding composition of  claim 1 . 
     
     
       10. An article prepared from the flame retardant molding composition of  claim 1  and shaped by injection molding, extrusion, blow molding, or vacuum forming. 
     
     
       11. A method for making a thermoplastic resin composition with excellent flame retardant characteristics when tested according to French norm NF-P-92-505, said method comprising. 
       a) preparing a masterbatch composition by mixing an aromatic carbonate resin with a guanidine sat, derivatives, or mixture thereof;  
       b) melt blending masterbatch composition produced in step a) wherein the guanidine salt, derivatives, or mixtures thereof is present in an amount of about 0.001 wt % to about 0.5 wt %, based on the total weight of the composition.  
     
     
       12. The method of  claim 11 , herein said guanidine salt or derivative is first dissolved in water before being mixed with said aromatic carbonate resin in preparing the masterbatch composition. 
     
     
       13. The composition of  claim 1  wherein when at least 10 specimens are prepared from said composition and tested according to French norm NF-P-92-505, they have a pass rate of at least 50% higher than specimens which do not contain said guandine salt, derivative or mixture thereof. 
     
     
       14. The method of  claim 7  wherein when at least 10 specimens are prepared from said composition and tested according to French norm NF-P-92-505, they have a pass rate of at least 50% higher than specimens which do not contain said guadine salt, derivative or mixture thereof. 
     
     
       15. The method of  claim 11  wherein when at least 10 specimens are prepared from said composition and tested according to French norm NF-P-92-505, they have a pass rate of at least 50% higher than specimens which do not contain said guanidine salt, derivative or mixture thereof. 
     
     
       16. A thermoplastic resin composition, comprising 
       a) an aromatic carbonate resin, and  
       b) about 0.001 wt % to about 0.5 wt % of a guanidine salt, derivatives or mixtures thereof, based on the total weight of the composition.  
     
     
       17. The composition of  claim 16 , wherein said aromatic carbonate resin is selected from the group consisting of homopolymers, copolymers, linear polycarbonate resins, braunlied polycarbonate resins, and mixtures thereof. 
     
     
       18. The composition of  claim 16 , wherein said guanidine salt is an inorganic salt. 
     
     
       19. The composition of  claim 16 , wherein said guanidine salt or derivatives is selected from the group consisting of aminoguanidine nitrate guanidine nitrate, triaminoguanidine nitrate, diaminoguanidine nitrate, guanidine carbonate, guanidine BPA, guanidine hydrochloride, guanidine bisulfite, guanidine sulfate, guanidine sulfamate, guanidine phosphate, guandine hydrobromide, and mixtures thereof. 
     
     
       20. The composition of  claim 16 , wherein said guanidine salt, derivative or mixture thereof is present in an amount of about 0.001 wt % to about 0.01 wt % based on